Diaphragm trimmer

ABSTRACT

A trimmer apparatus for removing flash from the inner diameter opening and the peripheral surface of a molded diaphragm. A molded diaphragm is placed on a rotatable fixture secured in a turret. Upon activation of an electrical switch the fixture is rotated to a press member station. In this location the turret is held stationary to allow a retractible member to engage a die member under the diaphragm to remove the flash from the inner diameter. In response to an operation signal the retractible member is raised from the die member and the turret is indexed to a cutting member. The cutting member presses the peripheral surface of the diaphragm against the fixture and is guided by the external surface of the diaphragm to simultaneously remove the flash from the outer edge of a diaphragm while the press member is in operation.

United States Patent Abbott et al.

DIAPHRAGM TRIMMER Malcolm K. Abbott; David A. Dowdy, both of Toledo, Ohio The Bendix Corporation Aug. 20, 1970 Inventors:

Assignee:

Filed:

Appl. No.:

References Cited UNITED STATES PATENTS 1,670,648 5/1928 Beyer ..83/274 X 1,994,178 3/1935 Raiche... ...83/9l4 X 2,839,306 6/1958 Bayles ..83/9l4 X \lllllll-Q 1 July 18, 1972 3,435,716 4/1969 Sjostrand ..83/4l1RX Primary Examiner-Frank T. Yost Attorney-William N. Antonis and Flame, l-lartz, Smith & Thompson ABSTRACT A trimmer apparatus for removing flash from the inner diameter opening and the peripheral surface of a molded diaphragm. A molded diaphragm is placed on a rotatable fixture secured in a turret. Upon activation of an electrical switch the fixture is rotated to a press member station. In this location the turret is held stationary to allow a retractible member to engage a die member under the diaphragm to remove the flash from the inner diameter. In response to an operation signal the retractible member is raised from the die member and the turret is indexed to a cutting member. The cutting member presses the peripheral surface of the diaphragm against the fixture and is guided by the external surface of the diaphragm to simultaneously remove the flash from the outer edge of a diaphragm while the press member is in operation.

10 Claims, 2 Drawing Figures PATENTED Jun 8 m 4/? PRESSURE EXHAUST INVENTORS MALCOLM K. ABBOTT DAV/0 A. 0014 0) DIAPHRAGM TRIMMER BACKGROUND OF THE INVENTION Rubber diaphragms made in press molds will have a small flash surrounding the periphery of the finished product. This occurs because, in order to assure a product without air pockets, more material than is needed is placed in the original mold.

In a prior art apparatus, removal of flash from the finished product was done by taking the finished product and, with a piece of abrasive, sanding the surface down. In the sanding process, if the material was not rotated or if the flash was not uniform, an unevenness on the surface would occur.

In another prior art apparatus, flash is removed by die stamping which is satisfactory when the diaphragm is relatively small but is cumbersome and massive as the diaphragm size increases. Further, in machines capable of die stamping the large diaphragms, a small misalignment centering of the diaphragm will result in a nonconcentric diaphragm, a wholly unsatisfactory product.

SUMMARY OF THE INVENTION In order to overcome the disadvantages of the prior art, we have invented a trimming apparatus for removing flash from a diaphragm which is compact and yet capable of simultaneously operating on a plurality of diaphragms.

In our device, a turret member, having a plurality of fixtures for holding a diaphragm, is sequentially rotated from a press station where flash from the inner diameter is removed to a cutting station which, guided by the periphery of the fixture, removes flash from the external surface of the diaphragm. In the sequential rotation, we have provided a gearing arrangement to permit the turret to stop when the fixture holding the diaphragm is under the press. While the turret is stopped, the cutting member simultaneously operates on another diaphragm to remove the flash from its external surface.

It is therefore an object of this invention to provide a trimmer apparatus with means to simultaneously remove flash from the inner diameter of a diaphragm at a press station while flash from the outer diameter of another diaphragm is removed at a cutting station.

It is another object to provide a trimmer apparatus with the means to adjust to a different size diaphragm member in order to remove flash.

These and other objects will become readily apparent to those of ordinary skill from reading the specification and viewing the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a prospective view of a trimmer apparatus for removing flash from a diaphragm constructed according to the principles of my invention with portions cut away for clarification.

FIG. 2 is a section taken along line 2--2 of FIG. I which shows the head section of the press member and the rotating knives of the cutting member in position to remove the flash from the diaphragm on the fixture member.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In the trimmer apparatus shown in FIG. 1, a housing 12 axially supports a turret member 14. A plurality of fixture members 16 secured to the turret 14 are intermittently rotated by gear means 18 from an initial station A, where a diaphragm D is placed on the fixture, to a press station B, where flash from the inner diameter of the diaphragm is removed, to a cutting station C, where flash from the outer diameter is removed, and to a final station D, where the diaphragm is removed in a condition ready for installation in a servomotor.

More particularly. gear means I8 includes a driver wheel 20 connected to the rotor shaft 22 of an electric motor and a driven wheel 24 connected to shaft 26 of the turret member 14. Driver wheel 20 carries a roller 28 that engages a slot 30 which causes the driven wheel 24 to rotate with a variable annular motion until the roller 28 leaves the slot 30. Driver wheel 20 is cut away near roller 28 to provide clearance for the spokes of driven wheel 24 in its motion. When the roller 28 leaves slot 30, driven wheel 24 will remain stationary until the driver wheel 20 has rotated to a position where engagement is made with a succeeding slot 31.

A disc shaped table 32 of the turret member 14 is attached to shaft 26 and retained in axial alignment in housing 12 by bearing member 34. In the disc shaped table 32 a plurality of openings 36 are equally spaced along a concentric arc with shaft 26. A fixture member 16 is placed in each opening 36.

Each fixture member 16 has a shaft 38 with a pad 40 attached to one end and a stop member 42 which rests on bearing means 44. Bearing means 44 is rigid enough to maintain shaft 38 in axial alignment with shaft 26 and yet allow the head member 46 to be rotated independently of the table 32. The head member 46 has a central retaining section 47, see FIG. 2. in axial alignment with shaft 38 and concentric ridges 48 which terminate in shelf 50. The particular position of ridges 48 and the number of ridges 48 will vary with the type of diaphragm to be trimmed while the die member 52 can be changed in the central retaining section to correspond to the inner diameter of the diaphragm. The annular projection 53 on the die member 52 corresponding to the particular size of the internal diameter of the diaphragm will engage bead 75 to guide the diaphragm into a secure fit with head 46.

At press station B a retractible cylinder member 54 is positioned in axial alignment with shaft 38 when the driven wheel 24 is disengaged from the driver wheel 20. Directly under the retractible cylinder member 54 is a raised section 39 which moves the stop member 42 away from the bearing means 44. With the stop member now moved away from bearing means 44, any force applied from the retractible head will shear the flash from the diaphragm without effect on the turret.

As the turret is rotated a trip switch adjacent the raised section of the section 39 is closed by pad 40. Upon closure of the switch, electricity will flow to solenoid 82 to move the armature 56 against the coil 58. The spool valve 60 attached to the armature will now prevent communication between the outlet port 62 and the atmosphere and permit communication between the inlet port 64 and a source of high air pressure. This high pressure will be communicated through port 66 to act on piston 68 in control chamber 69 of the retractible cylinder member 54. When this high pressure is large enough to overcome return spring 70, the retractible piston 68 is moved toward the die member 52 in the fixture. When the piston member 68 moves past a fixed point, sufficient for the annular rubber surface 91 of the head member 92 to contact die member 52 to shear the flash from a diaphragm in the control chamber 69, a relay switch 84 is activated by an adjustable contact 86, which will open the circuit to the solenoid and position the trip switch 80 to a ready position for activation. With coil 58 de-energized, spring 72 will move the spool valve 60 to close the inlet port 64 and open the outlet port 62. With outlet port 62 opened, return spring 70 will move piston 68 back to its initial position in the control chamber.

At cutting station C located on the housing 12 in a place tangent to the periphery of the fixture member 16, a pair of overlapping cutting knives 74 and 76 are adjustable either up or down or in or out by controls 75 and 77. This is to accommodate different types of fixture members. The first rotating knife 74 is positioned to overlie and press the diaphragm member 16 against the shelf 50, see FIG. 2. While the second rotating knife 76 will abut the periphery of the fixture to be guided in removing the flash 78 from the external surface, the first and second knives are rotated in opposite directions to be self feeding by pulling the material and thereby turning the fixture member 16 on the turret to assure that the flash is removed from the diaphragm. The electric motor 81 will rotate the cutting member at a constant speed to remove the external flash in a time less than the operation of the press station B.

MODE OF OPERATION OF THE PREFERRED EMBODIMENT In the embodiment shown in F IG. 1 at the initial station A, a diaphragm with flash from the molding process attached is taken from a supply (not shown) and placed on a fixture, as shown in FIG. 2. The rheostat 88, which controls the speed rotor shaft 22 of the electric motor 90 which operates the drive'wheel 20, is then placed in an on position. Drive wheel will rotate driven wheel 24 to rotate the turret holding fixture 16 into the press station B. During the rotation from station A to station B, the trip switch 80 will energize the solenoid valve 82 to permit high pressure to the control chamber 69. A time lag between the tripping of switch 80 and a complete stop of the turret at station B is provided in order that misalignment between the head member 92 and the die 52 is prevented.

At the same time the press operation at station B is being performed on a diaphragm, the flash 78 from the external diameter of a second diaphragm is being removed at station C by the oppositely rotating knives 74 and 76.

The time required for the driven wheel 20 to complete a cycle and engage the driven wheel 24 is adjusted by rheostat 88 to coincide with the movement of the piston 68 in the control chamber 69.

The succeeding diaphragms to be operated on are placed on fixture members while the turret is stopped during the press operation. The diaphragms, with the flash removed, are taken from the fixture at station D and placed in a container (not shown) for storage until needed.

Through our invention we have provided a trimmer apparatus which operates on each diaphragm member to remove flash in the same manner to provide a uniform diaphragm ready for installation.

We claim:

1. A trimmer apparatus for removing flash from an internal opening and an external surface of a diaphragm member, comprising:

a housing;

a turret member supported by said housing and having a plurality of fixture members, each of said fixture members having a rotatable head member, each of said rotatable head members having a central retaining section and a shelf on its periphery;

a die member retained in said central retaining section of each fixture member having a projection for positioning said diaphragm member on said fixture member;

a press member overlying said turret member having a retractible member which engages said diaphragm on said die member in response to an operational signal for removing said flash from said internal opening;

a cutting member guided by the periphery of said fixture member which engages said external surface of said diaphragm member to remove said flash by rotating said fixture member; and

means for rotating said turret in timed sequence from said press member to said cutting member.

2. The apparatus, as recited in claim 1, wherein each of said fixture members includes:

a shaft joined to said head member at one end thereof and extending through an opening in said turret member, said shaft having a pad at the other end thereof, said pad being adapted to rest on a raised section of said housing adjacent said press member in alignment with said retractible member to provide a firm support between said die member and said retractible member during engagement.

3. The apparatus, as recited in claim 2, including:

bearing means in said opening of said turret for maintaining said shaft in axial alignment and for permitting said head member to be rotated by said cutting member.

4. The apparatus as recited in claim 3, wherein said shaft includes:

a stop member which cooperates with said bearing means to prevent said shaft from contacting said housing during movement of said turret. 5. The apparatus, as recited In claim 4, wherein said press member includes:

a head member attached to said retractible member, said head member having an annular rubber surface which cooperates with said die member to shear said flash from said internal opening of said diaphragm.

6. The apparatus, as recited in claim 5, wherein said means for rotating includes:

gears for intermittingly indexing said turret; and

switching means connected to said press member for generating a signal to operate said retractible member in relation to the indexing position of said gears.

7. The apparatus, as recited in claim 6, wherein said cutting member includes:

a first rotating knife member;

a second oppositely rotating knife member adjacent said first rotating knife; and

means to'adjust the location of said first knife with respect to said fixture to urge said diaphragm against said shelf while said second knife abuts its peripheral surface.

8. The apparatus, as recited in claim 7, wherein said central retaining section of said fixture member will hold different size die members corresponding to different sizes of internal openings in the diaphragms.

9. The apparatus, as recited in claim 6, wherein said means for rotating includes:

an electrical member for controlling the rotational movement of said turret in relation to the amount of time required to operate said retractible member of said press member.

10. The apparatus, as recited in claim 9, wherein said cutting member is operated independently of said means for rotating said turret to remove flash from a diaphragm simultaneously with the operation of the retractible member of the press member. 

1. A trimmer apparatus for removing flash from an internal opening and an external surface of a diaphragm member, comprising: a housing; a turret member supported by said housing and having a plurality of fixture members, each of said fixture members having a rotatable head member, each of said rotatable head members having a central retaining section and a shelf on its periphery; a die member retained in said central retaining section of each fixture member having a projection for positioning said diaphragm member on said fixture member; a press member overlying said turret member having a retractible member which engages said diaphragm on said die member in response to an operational signal for removing said flash from said internal opening; a cutting member guided by the periphery of said fixture member which engages said external surface of said diaphragm member to remove said flash by rotating said fixture member; and means for rotating said turret in timed sequence from said press member to said cutting member.
 2. The apparatus, as recited in claim 1, wherein each of said fixture members includes: a shaft joined to said head member at one end thereof and extending through an opening in said turret member, said shaft having a pad at the other end thereof, said pad being adapted to rest on a raised section of said housing adjacent said press member in alignment with said retractible member to provide a firm support between said die member and said retractible member during engagement.
 3. The apparatus, as recited in claim 2, including: bearing means in said opening of said turret for maintaining said shaft in axial alignment and for permitting said head member to be rotated by said cutting member.
 4. The apparatus as recited in claim 3, wherein said shaft includes: a stop member which cooperates with said bearing means to prevent said shaft from contacting said housing during movement of said turret.
 5. The apparatus, as recited in claim 4, wherein said press member includes: a head member attached to said retractible member, said head member having an annular rubber surface which cooperates with said die member to shear said flash from said internal opening of said diaphragm.
 6. The apparatus, as recited in claim 5, wherein said means for rotating includes: gears for intermittingly indexing said turret; and switching means connected to said press member for generating a signal to operate said retractible member in relation to the indexing position of said gears.
 7. The apparatus, as recited in claim 6, wherein said cutting member includes: a first rotating knife member; a second oppositely rotating knife member adjacent said first rotating knife; and means to adjust the location of said first knife with respect to said fixture to urge said diaphragm against said shelf while said second knife abuts its peripheral surface.
 8. The apparatus, as recited in claim 7, wherein said central retaining section of said fixture member will hold different size die members corresponding to different sizes of internal openings in the diaphragms.
 9. The apparatus, as recited in claim 6, wherein said means for rotating includes: an electrical member for controlling the rotational movement of said turret in relation to the amount of time required to operate said retractible member of said press member.
 10. The apparatus, as recited in claim 9, wherein said cutting member is operated independently of said means for rotating said turret to remove flash from a diaphragm simultaneously with the operation of the retractible member of the press member. 